Honestly teaming shouldn't be bannable
because it can easily be countered by other people working together to try to take them out.
you all have a common goal in mind, take out the two people working together? so why don't you do it together?
you shouldn't ban someone for something just because the rest of the server isn't competent enough to learn to use teamwork as well to take them down.
now if the team is stalling the round when they're the last 2 alive and not killing each other, THAT should be bannable.